Apparatus for conveying roving in a textile machine



E. L. DOTTI Feb. 13, 1962 APPARATUS FOR CONVEYING ROVING IN A TEXTILE MACHINE Filed July 50,

' INVENTOR.

[07:7/0 [MM Z0 @0727 United States Patent 3,020,598 APPARATUS FOR CONVEYING ROVING IN A TEXTILE MACHINE Euterio L. Dotti, San Martin 2328, Santa Fe, Argentina Filed July 30, 1957, Ser. No. 675,182 2 Claims. (CI. 19-65) This invention relates to an apparatus to prevent the winding of fibres around rollers of textile machines of the high speed type, such as intersecting, gill-box, drawing frame, etc., used for doubling, combing and drawing the sliver of textile fibres. These preparing machines have front rollers that are driven and rotate in opposite directions, generally known as drawing or delivery rolls. The textile fibres are engaged between these rollers, and are drawn out from the combing devices.

In these modern machines, the high speed of roving feeding obtained, exceeds by more than five times the normal working speed of the older known machines. The electrostatic charges introduced into the material are increased due to higher speed of delivery, producing an increased friction between the combs and fibres and among the adjacent fibres themselves.

Considerable difliculty has been experienced in the high speed machines due to the fibres being electrostatically attracted to and clinging to the front drawing rollers of the machine. For instance, the fibres are wound around and cover the surface of the rollers, thereby eventually clog or otherwise produce stoppage of the machine. To overcome the above mentioned difliculty, the high speed machine has to slow down; the production capacity of the machine is consequently also reduced.

It has been found that the devices heretofore employed for dissipating these electro-static charges have been largely unsuccessful, even in the so-called low speed machines which have roller coverings made out of synthetic rubber. In these machines, when the delivery speed of the roving approaches 300 feet per minute, the winding of the roving around the drawing rollers cannot be prevented, even when operating the machine under proper humid conditions.

From the prolonged tests made with a modern gillbox type machine in which the fallers are driven by endless synchronized chains, as described in United States Patents 2,596,764 and 2,666,958, it was found that the machine could not be operated at a rate exceeding 300 feet per minute, because of the winding of roving around the drawing rollers.

It is an object of the present invention to prevent the winding of roving around the drawing rollers, thereby allowing an increase over the conventional operational speed of the machine. By incorporating applicants mechanism, a speed of delivery exceeding 450 feet per minute can easily be reached.

The invention, in general, refers to a conveyor mechanism being arranged immediately in front of the drawing rollers and before the funnel, which comprises at least one endless metallic conveyor for transporting the roving, one of the conveyor supporting and driving means being mounted at a minimum distance from the engagement zone of the drawing rollers, the electro-static charges produced in the handling of the fibres being thereby dissipated throughout the conveyor and grounded through the supporting means. The roving is fed to the funnel and then to the coiling can.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific embodiments when read in connection with the accompanying drawing in which:

FIG. 1 is a longitudinal section of one embodiment of the apparatus of the invention.

FIG. 2 is a perspective view of the apparatus of FIG. 1, and

FIG. 3 is a longitudinal section of another embodiment of the apparatus incorporating the features of the invention.

Referring now to the drawing, and initially to FIG. 1 and FIG. 2, in which the principal features of the invention are illustrated, there is a textile machine comprising gill bars A and drawing or delivery rollers 1, 2 and 3 of a high speed gill-box from which the roving 4 is delivered.

The apparatus to prevent the winding of fibres is arranged immediately in front of the drawing rollers 1, 2 and 3, and comprises the endless metallic conveyor 5, which is journalled around the sprocket wheels 6, 6 and sprocket or supporting roller 7, at least one of these two sprockets being driven to move the endless conveyor 5. The sprocket or supporting roller 7 must be of the smallest possible diameter in order to set the inlet zone of the endless conveyor 5 as close as possible to the delivery zone of the drawing rollers 2 and 3 from in between which the roving 4 emanates. can be of an equal or larger diameter as is illustrated in FIGS. 1 and 2. The axle of sprockets 6, 6 is provided with control means to vary the length of the conveyor. The feeding portion and the return portion of the conveyor can be guided by conventional tension rollers. The roving delivered by the apparatus is conveyed into the funnel and the coiling can provided in the machine.

The endless conveyor 5, as illustrated, comprises a pair of axially horizontal endless roller chains 8 and 8' that run parallel on spaced larger and smaller supporting gears or sprockets 6, 6' and 7. The opposite chain links are connected by rods 9 and form the conveying surface for the roving. The apparatus has cleaning devices 10 located in the path of the chains and rods, devices that are usually present in textile machines.

In the handling of fibrous material, the rotary speed of the gears or sprocket wheels 6 and 6' must be so regulated that the endless conveyor moves at a speed approximately equal to or slightly greater than the peripheral.

speed of the drawing rollers, 1, 2 and 3.

The roving fibres 4 that leave the drawing rollers are strongly pressed and electrically charged and move at great speed. These fibres will not tend to cling 'to the peripheral surface of the drawing'rollers 1, 2 and 3 and consequently wrap themselves around the rollers as normally happens with the known machines. The aforesaid disadvantages have been eliminated because the fibres are attracted by the rods 9 of the endless conveyor 5 of the apparatus according to my invention, which pass at a short distance from the rollers 1, 2 and 3.

When the roving fibres 4 get in touch with the rods 9, they dissipate the electro-static charges generated in the handling of the material, through the rods and chains, the latter being grounded. The roving fibres 4, which are now free of electro-static charges, are then transported by the endless conveyor to the funnel 11. The rods 9 move in a path that may be inclined from the rollers 2, 3 to the funnel 11. The roving fibres are projected at high speed from the rollers 2, 3 to the rapidly moving rods 9. Rods 9 generate upwardly moving air currents due to their high speed of movement. The air currents entrain the fibres projected from rollers 2, 3, separate the fibres and permit them to straighten out before impinging on the rods 9. The rods discharge the fibres electrically and convey them at high speed to the funnel 11.

Referring now to FIG. 3, the apparatus described to Patented Feb. 13-, 1962 The sprocket wheels 6, 6"

prevent the wrapping of fibres around drawing rollers of textile machines can also comprise a superposed endless pressure conveyor 12 similar to the conveyor 5, made up of roller chains 13 and rods, journalled around axially horizontal larger and smaller spaced supporting gears or sprockets 14 and 15, and having a cleaning device located in the path of the chains and rods. Both conveyors are arranged to move simultaneously, the rods of chains 12 being parallel to the rods of chain 5.

The roving which is usually positively charged is electrically attracted by the metallic rods of the apparatus. The roving is projected at high speed from rollers 2, 3 and is transported between the rods of both cooperating chains. The electro-static discharging effect of the apparatus is thereby improved.

Thus, the wrapping of the roving around drawing or delivery rollers 1, 2 and 3 is prevented and the consequent free action of the rollers allows a considerable increase in the operational speed of the machine, and a corresponding increase in the productive capacity of the machine.

While I have shown what I believe to be the best embodiments of my invention, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A conveying apparatus for roving in a yarn manufacturing machine including a funnel for receiving the roving, comprising in combination: cooperating drawing rollers driven at high speed to draw and project the rev ing at high speed in an electrically charged condition from the rollers, and means receiving and electrically discharging the roving while conveying the roving to the funnel; said means comprising axially parallel spaced Smaller and larger sprockets, the smaller of said sprockets being disposed adjacent the drawing rollers and the larger of said sprockets being disposed adjacent to the funnel, two spaced endless chains parallel in vertical planes entrained on the sprockets and driven at a linear speed not less than the peripheral speed of the drawing rollers, each of said chains including a plurality of links with overlapped ends, and rods respectively connecting each of the overlapped ends of the links of one chain with opposed overlapped ends of the links on the other chain, said rods and links being electrically conductive for electrically discharging the roving while carrying the roving to said funnel, said rods moving away from the drawing rollers in a path inclined upwardly from the smaller to the larger sprockets to entrain roving fibres projected from the drawing rollers, said rods creating upward currents of air to entrain and separate the fibres and to permit the fibres to straighten while being projected upon the rapidly moving rods.

2. A conveying apparatus for roving in a yarn manufacturing machine including a funnel for receiving the roving, comprising in combination: cooperating drawing rollers driven at high speed to draw and project the roving at high speed in an electrically charged condition from the rollers, and means receiving and electrically discharging the roving while conveying the roving to the funnel; said means comprising a first pair of axially parallel smaller and larger sprockets, the smaller of said sprockets being disposed adjacent to the drawing rollers and the larger sprockets being disposed adjacent to said funnel, two spaced endless chains disposed parallel in vertical planes entrained on the sprockets and driven at a linear speed not less than the peripheral speed of said drawing rollers, each of said chains including a plurality of links with overlapped ends, first rods respectively conmeeting each of the overlapped ends of the links of one chain with the opposed overlapped ends of the links on the other chain, said rods moving away from the drawing rollers in a path inclined upwardly from the smaller to the larger sprockets to entrain roving fibres projected from the rollers; a second pair of axially parallel spaced smaller and larger sprockets, the smaller of said second pair of sprockets being disposed adjacent to the drawing rollers and the larger of said second pair of sprockets being disposed adjacent to said funnel, two other spaced parallel chains entrained on the second sprockets and driven at said linear speed, each of the two other chains 1 including a plurality of links with overlapped ends, and

second rods respectivelly connecting each of the overlapped ends of the links of one of said two other chains with the opposed overlapped ends of the links on the other of said two other chains, all of said rods and links being electrically conductive and electrically discharging the roving fibres while the roving fibres are projected to and are drawn between juxtaposed groups of said first and second rods.

References Cited in the file of this patent UNITED STATES PATENTS 1,008,144 Hawley Nov. 7, 1911 1,598,952 Ansorg Sept. 7, 1926 1,636,977 Anderson July 26, 1927 2,228,794 Taine Jan. 14, 1941 2,258,661 Pool Oct. 14, 1941 2,468,827 Kennedy et a1. May 3, 1949 2,636,250 Hemmi Apr. 28, 1953 2,694,836 Peuto Nov. 23, 1954 FOREIGN PATENTS 699 Great Britain Feb. 20, 1878 362,810 Great Britain Dec. 10, 1931 

